SQL

Plsql Interview Questions And Answers 1. What is the starting "oracle error number"? 2)What is meant by forward declaration in functions?

2. Can Commit,Rollback ,Savepoint be used in Database Triggers?If yes than HOW? If no Why?With Reasons

3. Can we declare a column having number data type and its scale is larger than pricesion ex: column_name NUMBER (10,100), column_name NUMBAER(10,-84)

4. Explain how procedures and functions are called in a PL/SQL block ? 5. Explain the two type of Cursors ? 6. Explain the usage of WHERE CURRENT OF clause in cursors ? 7. Explian rowid,rownum?What are the pseduocolumns we have? 8. Give the structure of the function ? 9. Give the structure of the procedure ?

10. How many types of database triggers can be specified on a table ? What are they ? 11. How packaged procedures and functions are called from the following? a. Stored

procedure or anonymous block b. an application program such a PRC *C, PRO* COBOL c. SQL *PLUS

12. How to avoid using cursors? What to use instead of cursor and in what cases to do so? 13. How to debug the procedure ?

14. How to disable multiple triggers of a table at at a time? 15. How we can create a table in PL/SQL block. insert records into it??? is it possible by some procedure or function?? please give example...

16. How we can create a table through procedure ? 17. In a Distributed Database System Can we execute two queries simultaneously ? Justify ? 18. In pl/sql functions what is use of out parameter even though we have return statement. 19. Whar are Integarity Constraints?

20. Is it possible to use Transaction control Statements such a ROLLBACK or COMMIT in Database Trigger ? Why ?

21. Name the tables where characteristics of Package, procedure and functions are stored ? 22. Open C1; Fetch c1 into Z; Commit; Fetch c1 in to Z; end; 23. State the advantage and disadvantage of Cursor? 24. State the difference between implicit and explicit cursor's. 25. What are % TYPE and % ROWTYPE ? What are the advantages of using these over datatypes? 26. What are advantages fo Stored Procedures 27. What are the PL/SQL Statements used in cursor processing ?

28. What are the Restrictions on Cursor Variables? 29. What are the components of a PL/SQL Block ? 30. What are the cursor attributes used in PL/SQL ? 31. What are the datatypes a available in PL/SQL ? 32. What are the modes of parameters that can be passed to a procedure ?

33. What are the return values of functions SQLCODE and SQLERRM ? 34. What are the two parts of a procedure ? 35. What are two parts of package ?

36. What are two virtual tables available during database trigger execution ? 37. What happens if a procedure that updates a column of table X is called in a database trigger of the same table ?

38. What is Overloading of procedures ? 39. What is PL/SQL ? 40. What is PL/SQL table ? 41. What is Pragma EXECPTION_INIT ? Explain the usage ? 42. What is Raise_application_error ? 43. What is a cursor ? Why Cursor is required ? 44. What is a cursor for loop ?

45. What is a database trigger ? Name some usages of database trigger ? 46. What is a stored procedure ? 47. What is an Exception ? What are types of Exception ? 48. What is difference between % ROWTYPE and TYPE RECORD ? 49. What is difference between a Cursor declared in a procedure and Cursor declared in a package specification ? 50. What is difference between a PROCEDURE & FUNCTION ? 51. What is difference between stored procedures and application procedures,stored function and application function? 52. What is pl/sql?what are the advantages of pl/sql? 53. What is ref cursor. 54. What is the basic structure of PL/SQL ?

55. What is trigger,cursor,functions in pl-sql and we need sample programs about it? 56. What will happen after commit statement ? 57. What will the Output for this Coding> Declare Cursor c1 is select * from emp FORUPDATE; Z c1%rowtype; Begin 58. Where the Pre_defined_exceptions are stored ?

59. Write the order of precedence for validation of a column in a table ? I. done using Database triggers. ii. done using

SQL General Interview Questions ... •

What are the different types of joins?

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Explain normalization with examples.

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What cursor type do you use to retrieve multiple recordsets?

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Diffrence between a "where" clause and a "having" clause

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How will you copy the structure of a table without copying the data?

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How to find out the database name from SQL*PLUS command prompt?

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Tadeoffs with having indexes

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Talk about "Exception Handling" in PL/SQL?

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What is the diference between "NULL in C" and "NULL in Oracle?"

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What is Pro*C? What is OCI?

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Give some examples of Analytical functions.

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What is the difference between "translate" and "replace"?

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What is DYNAMIC SQL method 4?

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How to remove duplicate records from a table?

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What is the use of ANALYZing the tables?

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How to run SQL script from a Unix Shell?

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What is a "transaction"? Why are they necessary?

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Explain Normalizationa dn Denormalization with examples.

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When do you get contraint violtaion? What are the types of constraints?

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How to convert RAW datatype into TEXT?

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Difference - Primary Key and Aggregate Key

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How functional dependency is related to database table design?

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What is a "trigger"?

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Why can a "group by" or "order by" clause be expensive to process?

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What are "HINTS"? What is "index covering" of a query?

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What is a VIEW? How to get script for a view?

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What are the Large object types suported by Oracle?

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What is SQL*Loader?

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Difference between "VARCHAR" and "VARCHAR2" datatypes.

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What is the difference among "dropping a table", "truncating a table" and "deleting all records" from a table.

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Difference between "ORACLE" and "MICROSOFT ACCESS" databases.

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How to create a database link ?

PL/SQL interview questions... •

Normalize many to many relationships

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Difference - Equijoin and union -- Sponsored Links -Your Ad Here

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What is TEMP table space in Oracle, what is rollback segment

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How do we find row chaining?

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Pattern matching operators

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Features in oracle 9i and 10g

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Why truncating table is faster than delete

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copy commit syntax

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Convert Zulu time zone to US Eastern time zone

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Difference - union and union all

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Difference - Group by, Order by clause

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Which Ranking functions are available?

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Difference - Decode, NVL, NVL2

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Tradeoffs of using partitioned tables

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How can we call stored procedure in SQL query

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What are the restrictions on calling PL/SQL from SQL

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Why EXISTS is preferable to distinct

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Give two examples of avoiding unnecessary parsing.

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Can a Tablespace hold objects from different Schemes ?

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Can a View based on another View ?

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Can a property clause itself be based on a property clause?

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Can a tablespace hold objects from different schemes?

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Can a view based on another view?

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Can objects of the same Schema reside in different tablespaces.?

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Can one export to multiple files?/ Can one beat the Unix 2 Gig limit? (for DBA

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Can one import/export between different versions of Oracle? (for DBA

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Can one rename a database user (schema)?

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Can you have more than one content canvas view attached with a window?

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Can you pass data parameters to forms?

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Define Transaction ?

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Describe two phases of Two-phase commit ?

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Differentiate simple and complex, snapshots ?

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Do View contain Data ?

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Do a view contain data?

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Do user parameters appear in the data modal editor in 2.5?

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Does Oracle write to data files in begin/hot backup mode? (for DBA

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Does a Before form trigger fire when the parameter form is suppressed?

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Does a grouping done for objects in the layout editor affect the grouping done in the data model editor?

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Does one need to drop/ truncate objects before importing? (for DBA

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EXIT_FORM is a restricted package procedure ?a. True b. False

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Explain about horizontal, Vertical tool bar canvas views?

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Explain about stacked canvas views?

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Explain the relationship among Database, Tablespace and Data file.?

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Explain the relationship among database, tablespace and data file.

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From which designation is it preferred to send the output to the printed?

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Give the sequence of execution of the various report triggers?

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How are extents allocated to a segment?

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How are the index updates?

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How can I message to passed to the user from reports?

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How can a break order be created on a column in an existing group? What are the various sub events a mouse double click event involves?

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How can a button be used in a report to give a drill down facility?

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How can a group in a cross products be visually distinguished from a group that does not form a cross product?

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How can a square be drawn in the layout editor of the report writer?

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How can a text file be attached to a report while creating in the report writer?

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How can one dump internal database structures? (for DBA

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How can one improve Import/ Export performance? (for DBA

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How can one see who is using a temporary segment? (for DBA

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How can values be passed bet. precompiler exits and Oracle call interface?

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How can we reduce the network traffic?

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How can we specify the Archived log file name format and destination?

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How can you Enforce Referential Integrity in snapshots ?

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How can you enable automatic archiving ?

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How do I find used/free space in a TEMPORARY tablespace?

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How do you control the constraints in forms ?

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How do you create a new session while open a new form?

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How do you display console on a window ?

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How do you reference a Parameter?

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How do you reference a parameter indirectly?

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How do you trap the error in forms 3.0 ?

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How does Space allocation table place within a block ?

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How does one add users to a password file? (for DBA

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How does one backup a database using RMAN? (for DBA

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How does one backup archived log files? (for DBA

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How does one coalesce free space?

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How does one connect to an administrative user? (for DBA

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How does one create a RMAN recovery catalog? (for DBA

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How does one create a new database?

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How does one create a password file? (for DBA

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How does one do off-line database backups? (for DBA

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How does one do on-line database backups? (for DBA

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How does one get the view definition of fixed views/tables?

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How does one prevent tablespace fragmentation?

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How does one put a database into ARCHIVELOG mode? (for DBA

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How does one see the uptime for a database? (for DBA

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How free extents are managed in Ver 6.0 and Ver 7.0 ?

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How is it possible to select generate a select set for the query in the query property sheet?

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How is link tool operation different bet. reports 2 & 2.5?

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How many pages you can in a single form ?

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How many windows in a form can have console?

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How to define Data Block size ?

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How to implement the multiple control files for an existing database ?

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How will you create multiple rollback segments in a database ?

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How will you enforce security using stored procedures?

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How will you estimate the space required by a non-clustered tables?

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How will you force database to use particular rollback segment ?

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How will you monitor rollback segment status ?

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How will you monitor the space allocation ?

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How will you swap objects into a different table space for an existing database ?

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I've lost my REDOLOG files, how can I get my DB back? (for DBA

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I've lost some Rollback Segments, how can I get my DB back? (for DBA

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If a break order is set on a column would it affect columns which are under the column?

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If a parameter is used in a query without being previously defined, what diff. exist betw. report 2.0 and 2.5 when the query is applied?

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If two groups are not linked in the data model editor, What is the hierarchy between them?

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Is it possible to link two groups inside a cross products after the cross products group has been created?

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Is it possible to modify an external query in a report which contains it?

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Is the After report trigger fired if the report execution fails?

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It is possible to use raw devices as data files and what is the advantages over file. system files ?

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List the Optional Flexible Architecture (OFA) of Oracle database? or How can we organize the tablespaces in Oracle database to have maximum performance ?

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My database is down and I cannot restore. What now? (for DBA

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My database was terminated while in BACKUP MODE, do I need to recover? (for DBA

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Name of the functions used to get/set canvas properties?

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State any three mouse events system variables?

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To display the page no. for each page on a report what would be the source & logical page no. or & of physical page no.?

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To execute row from being displayed that still use column in the row which property can be used?

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Use the Add_group_row procedure to add a row to a static record group 1. true or false?

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WWhat is the use of ANALYZE command ?

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What are Clusters ?

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What are Most Common types of Complex master-detail relationships?

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What are Roles ?

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What are Schema Objects?

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What are built-ins associated with timers?

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What are built-ins used for Processing rows?

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What are clusters?

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What are different types of canvas views?

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What are different types of images?

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What are different types of modules available in oracle form?

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What are disadvantages of having raw devices ?

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What are modal windows?

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What are parameters?

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What are roles? How can we implement roles ?

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What are synonyms used for?

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What are the Built-ins used for sending Parameters to forms?

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What are the Characteristics of Data Files ?

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What are the Coordination Properties in a Master-Detail relationship?

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What are the Referential actions supported by FOREIGN KEY integrity constraint ?

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What are the advantages of views?

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What are the basic element of Base configuration of an oracle Database ?

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What are the benefits of distributed options in databases?

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What are the built -ins used for Modifying a groups structure?

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What are the built-in used for getting cell values?

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What are the built-ins that are used for setting the LOV properties at runtime?

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What are the built-ins that are used to Attach an LOV programmatically to an item?

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What are the built-ins used for Creating and deleting groups?

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What are the built-ins used for Getting cell values?

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What are the built-ins used for finding Object ID function?

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What are the built-ins used for finding object ID functions?

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What are the built-ins used for processing rows?

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What are the common Import/ Export problems? (for DBA

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What are the components of logical database structure of Oracle database?

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What are the components of physical database structure of Oracle database?

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What are the database administrators utilities avaliable ?

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What are the default extensions of the files created by forms modules?

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What are the default extensions of the files created by library module?

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What are the default extensions of the files created by menu module?

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What are the default parameter that appear at run time in the parameter screen? What are the various sub events a mouse double click event involves?

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What are the dictionary tables used to monitor a database space?

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What are the dictionary tables used to monitor a database spaces ?

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Difference between lov & list item?

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Differences between EBU and RMAN? (for DBA

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Different Levels of Auditing ?

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Different Parameter types?

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Different approaches used by Optimizer in choosing an execution plan ?

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Different default triggers created when Master Deletes Property is set to Cascade?

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Different default triggers created when Master Deletes Property is set to Non-isolated?

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Different default triggers created when Master Deletes Property is set to isolated?

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Different display styles of list items?

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Different file extensions that are created by oracle reports?

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Different kind of export backups?

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Different methods of backing up oracle database ?

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Different modals of windows?

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Different styles of activation of ole Objects?

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Different type of Segments ?

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Different types of Delete details we can establish in Master-Details?

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Different types of Record Groups?

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Different windows events activated at runtimes?

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What are the factors causing the reparsing of SQL statements in SGA?

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What are the master-detail triggers?\

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What are the options available to refresh snapshots ?

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What are the sql clauses supported in the link property sheet?

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What are the system resources that can be controlled through Profile ?

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What are the three types of user exits available ?

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What are the trigger associated with image items?

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What are the two panes that Appear in the design time pl/sql interpreter?

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What are the two phases of block coordination?

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What are the two repeating frame always associated with matrix object?

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What are the two types of views available in the object navigator(specific to report 2.5)?

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What are the two ways by which data can be generated for a parameters list of values?

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What are the type of Synonyms?

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What are the types of Pop-up window ?

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What are the types of calculated columns available?

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What are the types of synonyms?

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What are the use of Roles ?

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What are the various methods of performing a calculation in a report ?

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What are the various sub events a mouse double click event involves? What are the various sub events a mouse double click event involves?

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What are the various type of snapshots?

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What are the vbx controls?

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What are the ways to monitor the performance of the report?

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What are three panes that appear in the run time pl/sql interpreter?

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What are visual attributes?

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What database aspects should be monitored? (for DBA

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What database block size should I use?

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What database events can be set? (for DBA

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What does COMMIT do ?

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What does ROLLBACK do ?

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What does a Control file Contain ?

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What dynamic data replication?

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What is Auditing ?

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What is COST-based approach to optimization ?

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What is Database Buffers ?

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What is Distributed database ?

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What is Full Backup ?

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What is Index Cluster ?

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What is Mirrored on-line Redo Log ?

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What is Object Auditing ?

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What is Oracle table?

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What is Parallel Server ?

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What is Partial Backup ?

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What is Privilege Auditing ?

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What is Read-Only Transaction ?

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What is Rollback Segment ?

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What is SGA?

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What is SYSTEM tablespace and when is it created?

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What is Statement Auditing ?

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What is Table ?

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What is Tablespace Quota ?

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What is Two-Phase Commit ?

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What is WHEN-Database-record trigger?

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What is a Control file ?

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What is a Database instance ? Explain

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What is a Redo Log ?

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What is a Rollback segment entry ?

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What is a SNAPSHOT ?

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What is a SNAPSHOT LOG ?

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What is a SQL * NET?

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What is a Schema ?

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What is a Shared SQL pool?

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What is a Static Record Group?

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What is a Tablespace?

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What is a Text_io Package?

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What is a User_exit?

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What is a View ?

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What is a cluster Key ?

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What is a combo box?

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What is a data segment?

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What is a database EVENT and how does one set it? (for DBA

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What is a deadlock ? Explain .

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What is a difference between pre-select and pre-query?

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What is a logical backup?

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What is a physical page ? & What is a logical page ?

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What is a private synonym?

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What is a profile ?

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What is a property clause?

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What is a public synonym?

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What is a record group?

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What is a shared pool?

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What is a synonym?

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What is a tablespace?

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What is a text list?

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What is a timer?

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What is advantage of having disk shadowing/ Mirroring ?

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What is an Extent ?

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What is an Index ?

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What is an Index ? How it is implemented in Oracle Database ?

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What is an Index Segment ?

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What is an Integrity Constrains ?

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What is an LOV?

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What is an Oracle index?

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What is an Oracle sequence?

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What is an Oracle view?

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What is an SQL *FORMS ?

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What is an administrative (privileged) user? (for DBA

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What is an object group?

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What is an user exit used for?

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What is bind reference and how can it be created?

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What is cluster key?

•

What is clusters ?

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What is cold backup? What are the elements of it?

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What is coordination Event?

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What is default tablespace ?

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What is dictionary cache ?

•

What is difference between UNIQUE constraint and PRIMARY KEY constraint ?

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What is difference between open_form and call_form?

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What is forms_DDL?

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What is hot backup and how it can be taken?

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What is lexical reference? How can it be created?

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What is mean by Program Global Area (PGA)?

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What is meant by Redo Log file mirroring ? How it can be achieved?

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What is meant by free extent ?

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What is meant by recursive hints ?

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What is meant by redo log buffer ?

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What is new_form built-in?

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What is pop list?

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What is relation between the window and canvas views?

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What is schema?

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What is snapshot log ?

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What is snapshots?

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What is strip sources generate options?

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What is synchronize?

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What is system.coordination_operation?

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What is term?

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What is the "LOV of Validation" Property of an item? What is the use of it?

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What is the Maximum allowed length of Record group Column?

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What is the User-Named Editor?

•

What is the advantage of the library?

•

What is the basic data structure that is required for creating an LOV?

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What is the diff. bet. setting up of parameters in reports 2.0 reports2.5?

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What is the diff. when Flex mode is mode on and when it is off?

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What is the diff. when confine mode is on and when it is off?

•

What is the difference between OLE Server & Ole Container?

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What is the difference between ON-VALIDATE-FIELD trigger and a POST-CHANGE trigger ?

•

What is the difference between SHOW_EDITOR and EDIT_TEXTITEM?

•

What is the difference between locks, latches, enqueues and semaphores? (for DBA

•

What is the difference between object embedding & linking in Oracle forms?

•

What is the effect of setting the value "ALL_ROWS" for OPTIMIZER_GOAL parameter of the ALTER SESSION command ? What are the factors that affect OPTIMIZER in choosing an Optimization approach ?

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What is the effect of setting the value "CHOOSE" for OPTIMIZER_GOAL, parameter of the ALTER SESSION Command ?

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What is the frame & repeating frame?

•

What is the maximum no of chars the parameter can store?

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What is the mechanism provided by ORACLE for table replication ?

•

What is the purpose of the product order option in the column property sheet?

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What is the remove on exit property?

•

What is the significance of having storage clause ?

•

What is the usage of an ON-INSERT,ON-DELETE and ON-UPDATE TRIGGERS ?

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What is the use of ANALYSE ( Ver 7) option in EXP command ?

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What is the use of COMPRESS option in EXP command ?

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What is the use of CONSISTENT (Ver 7) option in EXP command ?

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What is the use of CONSTRAINTS option in EXP command ?

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What is the use of Control File ?

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What is the use of FILE option in IMP command ?

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What is the use of FULL option in EXP command ?

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What is the use of GRANT option in EXP command?

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What is the use of GRANT option in IMP command ?

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What is the use of IGNORE option in IMP command ?

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What is the use of INCTYPE option in EXP command ?

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What is the use of INDEXES option in EXP command ?

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What is the use of INDEXES option in IMP command ?

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What is the use of PARFILE option in EXP command ?

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What is the use of RECORD LENGTH option in EXP command ?

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What is the use of RECORD option in EXP command?

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What is the use of ROWS option in EXP command ?

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What is the use of ROWS option in IMP command ?

•

What is the use of SHOW option in IMP command ?

•

What is the use of hidden column? What are the various sub events a mouse double click event involves?

•

What is the use of image_zoom built-in?

•

What is the use of place holder column? What are the various sub events a mouse double click event involves?

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What is the use of transactional triggers?

•

What is trigger associated with the timer?

•

What is use of term?

•

What is user Account in Oracle database?

•

What third party tools can be used with Oracle EBU/ RMAN? (for DBA

•

What use of command line parameter cmd file?

•

When do you use data parameter type?

•

When is PRE-QUERY trigger executed ?

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When will the data in the snapshot log be used?

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Where are my TEMPFILES, I don't see them in V$DATAFILE or DBA_DATA_FILE? (for DBA

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Where can one find the high water mark for a table?

•

Where can one get a list of all hidden Oracle parameters? (for DBA

•

Where is a procedure return in an external pl/sql library executed at the client or at the server?

•

Where is the external query executed at the client or the server?

•

Where should the tuning effort be directed? (for DBA

•

Which of the above methods is the faster method?

•

Which of the two views should objects according to possession?

•

Which parameter can be used to set read level consistency across multiple queries?

•

Which parameter in Storage clause will reduce no. of rows per block?

•

While specifying master/detail relationship between two blocks specifying the join condition is a must ? True or False. ?

•

Why and when should one tune? (for DBA

•

Why are OPS$ accounts a security risk in a client/server environment? (for DBA

•

Why is it preferable to create a fewer no. of queries in the data model?

•

Why query fails sometimes ?

•

With which function of summary item is the compute at options required?

•

what are difference between post database commit and post-form commit?

INDEX - Indexes help us retrieve data from tables quicker. Let's use an example to illustrate this point: Say we are interested in reading about how to grow peppers in a gardening book. Instead of reading the book from the beginning until we find a section on peppers, it is much quicker for us to go to the index section at the end of the book, locate which pages contain information on peppers, and then go to these pages directly. Going to the index first saves us time and is by far a more efficient method for locating the information we need. The same principle applies for retrieving data from a database table. Without an index, the database system reads through the entire table (this process is called a 'table scan') to locate the desired

information. With the proper index in place, the database system can then first go through the index to find out where to retrieve the data, and then go to these locations directly to get the needed data. This is much faster. Therefore, it is often desirable to create indexes on tables. An index can cover one or more columns. The syntax for creating a table index is shown in the CREATE INDEX section. Below we discuss some general strategies when building and using an index: 1. Build index on columns of integer type Integers take less space to store, which means the query will be faster. If the column you want to build an index for is not of type integer, consider creating a surrogate integer key (or simply a surrogate column of type integer) which maps one-to-one to the column you want to build the index for. 2. Keep index as narrow as possible Narrower indexes take less space, require less time to process, which in turn means the query will run faster. 3. Column order is important For indexes covering multiple columns, the order of the columns in the index is important. The best practice is to use the column with the lowest cardinality first, and the column with the highest cardinality last. Recall cardinality means the number of distinct values for that column. So, if "SELECT DISTINCT (COLUMN1) FROM TABLE_NAME;" returns 5, that means the cardinality for COLUMN1 is 5. 4. Make sure the column you are building an index for is declared NOT NULL This can decrease the size of the index, which in turn will speed up the query. VIEW – A view is a virtual table. A view consists of rows and columns just like a table. The difference between a view and a table is that views are definitions built on top of other tables (or views), and do not hold data themselves. If data is changing in the underlying table, the same change is reflected in the view. A view can be built on top of a single table or multiple tables. It can also be built on top of another view. In the SQL Create View page, we will see how a view can be built. Views offer the following advantages: 1. Ease of use: A view hides the complexity of the database tables from end users. Essentially we can think of views as a layer of abstraction on top of the database tables. 2. Space savings: Views takes very little space to store, since they do not store actual data. 3. Additional data security: Views can include only certain columns in the table so that only the nonsensitive columns are included and exposed to the end user. In addition, some databases allow views to have different security settings, thus hiding sensitive data from prying eyes.